Flock is used in the manufacture of numerous types of articles, such as textiles. Such articles are typically manufactured by electrostatically depositing the flock onto the desired surface. In one process, the desired surface is a release-adhesive coated sacrificial carrier sheet. The free ends of the flock are then contacted with an adhesive. This structure, also known as a transfer, is thermally applied to the substrate. In another process, the desired surface is a permanent adhesive or the substrate itself. This process is known as direct flocking. The direct flocked structure generally does not include a carrier sheet and release adhesive.
Flock fibers are either pre-dyed (before application to the desired surface) or post-dyed (after application to the surface). Post-dyeing is typically effected by sublimation dyeing techniques in which the flock and dye are heated so that the vaporized dye is transferred to the flock fiber. A sublimation print in the desired design typically carries the dye for transfer to the flock either by inkjet or heat transfer techniques. As used herein, “sublimation” refers to a process where an image is printed by turning dye, ink or toner by heat and/or pressure into a gas which then impregnates itself into a substrate or a coating on a substrate.
The use of sublimation printing of flock has generally not been widely practiced for various reasons. Some polyesters, such as poly(ethylene terephthalate), can hold the dye but have little loft retention and flatten out during sublimation printing. Other polyesters typically melt or soften and deform under the high temperatures experienced during sublimation printing, losing desirable tactile characteristics (soft touch). Nylon and rayon fibers, though having loft retention, generally are unable to accept the vaporized dye consistently and/or permanently and therefore produce an irregular and/or unstable colored product.